排序方式： 共有41条查询结果，搜索用时 31 毫秒
21.
Marcela P. Bagagli Sahar Jazaeri Jayne E. Bock Koushik Seetharaman Helia H. Sato 《Cereal Chemistry》2014,91(5):460-465
Transglutaminase (TGase) can improve the functional characteristics of proteins by introducing covalent bonds inter‐ or intrachains. Temperature and pH interfere with the protein structure and the catalytic activity of enzymes. Because these three factors can act synergistically, TGase, citrate buffer, and temperature were evaluated for their effects on the rheological and chemical changes in low‐protein wheat flour dough. Dough strength, measured by microextension test, significantly increased with increasing levels of TGase (8 U/g of protein), with changes in pH of the citrate buffer (pH 6.5), and by the effect of interaction between these factors. The same trend was observed in the size‐exclusion HPLC measurements, indicating that these two parameters have the effect of increasing gluten protein aggregation. Temperature had a significant effect on dough extension, measured by microextension test. The changes in secondary structure of gluten protein were investigated by FTIR second‐derivative spectra (amide I region, 1,600–1,700 cm−1) and showed an increase in β‐sheet structures initiated by TGase, citrate buffer pH, and their interaction. 相似文献
22.
Manal A. A. Afifi Magdy F. El-Kady Sahar A. Zoelfakar Ahmed Sayed Abddel-Moneim 《Tropical animal health and production》2013,45(2):687-690
Multiple avian influenza viruses’ subtypes are circulating worldwide possessing serious threat to human populations and considered key contributors to the emergence of human influenza pandemics. This study aimed to identify the potential existence of H7 and H9 avian influenza infections circulating among chicken flocks in Egypt. Serum samples were collected from chicken flocks that experienced respiratory distresses and/or variable mortality rates. H7 and H9 virus infections were screened by haemagglutination inhibition assay using chicken erythrocytes. Serum samples were collected from 9 broiler, 12 breeder and 18 layer flocks. Out of 1,225 examined sera, 417 (34 %) from 14 flocks and 605 (49.4 %) from 21 flocks were found positive for H7 and H9, respectively. Prevalence of both H7 and H9 antibodies were higher in layer followed by breeder then broiler flocks. Special consideration should be paid to control influenza viruses in Egypt, as pandemic influenza strains may develop unnoticed given the presence of subclinical infections, and the possibility of re-assortment with the prevailing endemic H5N1 virus strains in Egypt do exist. 相似文献
23.
In this paper, a viscoelastic model for the recovery behavior of the machine-made carpet has been presented. Different combinations of spring and dashpot systems are usually considered to model the mechanical behavior of textile materials. The initial thickness of the carpet samples was measured using a digital thickness gauge. The samples were then imposed to static loading. Consequently, the thickness of carpet samples after the load removal was measured again by considering the relaxation time at the range of 1 to 30 minutes with the intervals of 2 minutes. Jeffery’s mechanical model, which is combined of spring and dashpot components, was used to model the variation trend of thickness loss percentages for the carpet samples at different relaxation times. Curve fitting based on the least square method was used to adapt the experimental data to the theoretical model. For comparison, the standard linear model was also applied to experimental data. The results showed that there was a reasonably good agreement between the Jeffrey’s model and the experimental data. The results also revealed the linear standard model showed poor regression for the recovery properties of cut pile carpets after static loading. The reason was that the standard linear model was completely elastic, showing no secondary creep. On the other hand, the recovery of cut pile carpers showed some permanent creep that could be explained by Jeffrey’s model. 相似文献
24.
25.
Pathogenic microorganisms are commonly associated with external ocular infections in birds. Pathogen virulence factors as well as reduced host defenses resulting from poor living conditions, nutrition, genetics, physiology, hygiene, fever, and age may increase host susceptibility. Staphylococcus species are bacteria known to serve as opportunistic pathogens in eye infections. The changing profile of microorganisms involved in ocular infections and the emergence of acquired microbial resistance dictate the need for investigative studies regarding bacterial profiles and antimicrobial susceptibility patterns for external ocular infections. The aim of this study was to determine the prevalence of Staphylococcus aureus ocular infections in pigeons and to evaluate their biofilm production ability and antibiotic resistance patterns. Twenty pigeons with confirmed eye infections were included in this project. Conjunctival specimens were collected with swabs presoaked in sterile normal saline. Bacterial growth was identified by standard laboratory procedures and susceptibility testing of the isolates was performed by the Kirby-Bauer method. The ability of the isolates to form a biofilm was also assessed using the microtiter plate method. Of the 20 specimens processed, 20% of the pigeons had staphylococcal eye infections. The resistance pattern of these isolates showed that Staphylococcus spp. from pigeon samples were resistant to tetracycline (100%), erythromycin (100%), azithromycin (100%), nalidixic acid (100%), and cefazolin (50%). All of the Staphylococcus spp. isolated from the pigeons were susceptible to gentamycin and furazolidone. The results of the biofilm detection test showed that 75% of the isolates were biofilm producers. In conclusion, biofilm forming S. aureus with multidrug resistance patterns were the most prevalent bacteria isolated from the pigeons examined in this research study. 相似文献
26.
Mohamed M. Zeweil Kadry M. Sadek Mohamed F. Elsadek Sahar F. Mahmoud Badreldin M. Ahmed Asmaa F. Khafaga 《Animal Science Journal》2020,91(1)
Liver fibrosis is a major health concern, which might progress to cirrhosis. To date, treatment trials rely mainly on the removal of the causative factor. The current study investigated the potential ameliorative role of sidr honey on thioacetamide (TAA)‐induced liver fibrosis in rats. Forty‐eight Wistar albino rats were equally allocated into four groups: control; sidr honey (5g/kg body weight (BW), orally); TAA (200 mg/kg BW, IP three times weekly/15 weeks); and sidr honey plus TAA at the same dose and administration rout. Rats co‐treated with sidr honey plus TAA revealed significant reduction in hepatic malondialdehyde, hyaluronic acid (HA), alanine aminotransferase, aspartate aminotransferase, alkaline phosphatase, gamma glutamyl transferase, direct bilirubin, and hepatic mRNA expression of transforming growth factor (TGF)‐β1 and collagen type I alpha 1 chain (COL1a1) compared to TAA‐exposed rats. In addition, the hepatoprotective potential of sidr honey was indicated via improvement of histopathologic picture of hepatocytes and upregulation of total antioxidant capacity, reduced glutathione, catalase, glutathione peroxidase, superoxide dismutase, total protein, and albumin compared to TAA‐treated rats. In conclusion, daily administration of sidr honey (5 g/kg BW) is a promising natural antioxidant and fibrosuppressive agent that could ameliorate liver fibrosis via downregulation of fibrosis genes including TGF‐β1 and COL1a1 and HA and via enhancement of antioxidant system. 相似文献
27.
Nawwar M Hussein S Ayoub N Hashim A El-Sharawy R Lindequist U Harms M Wende K 《Fitoterapia》2011,82(8):1265-1271
Assessment of the UV protecting potential of an aqueous methanol leaf extract of Harpephyllum caffrum proved that it possesses a distinct radical scavenging effect and inhibits the production of the proinflammatory cytokine IL-6 by human keratinocytes (HaCaT cells) following UV radiation. Phytochemical investigation of this extract led to isolation and structural determination of the hitherto unknown phenolics, kaempferol 3-O-(2″-sulphatogalactopyranoside), its quercetin analogue and 3-methoxyellagic acid 4-O-galactopyranoside in addition to 18 known phenolic compounds. The structures were determined by spectroscopic and conventional methods of analysis. Flavonoid sulphatoglycosides which have been rarely found in nature were major phenolic constituents of this plant, and this is the first report of the isolation of any of them from Anacardiaceae. The extract was found to diminish UV phototoxic reaction of keratinocytes. However, the isolated kaempferol sulphatogalactopyranoside did not interact with UVB triggered IL-6 production of HaCaT keratinocytes. 相似文献
28.
Hamarashid Sahar Hussein Khaledian Yasin Soleimani Faranak 《Genetic Resources and Crop Evolution》2022,69(2):719-728
Genetic Resources and Crop Evolution - Lamb’s-ear (Stachys byzantina L.) serves as valuable medicinal plant mainly because of its pharmaceutical phyto-metabolites like linalool. Polyploidy... 相似文献
29.
Sahar Jazaeri Jayne E. Bock Marcela P. Bagagli Stefania Iametti Francesco Bonomi Koushik Seetharaman 《Cereal Chemistry》2015,92(1):105-113
The network‐forming attributes of gluten have been investigated for decades, but no study has comprehensively addressed the differences in gluten network evolution between strong and weak wheat types (hard and soft wheat). This study monitored changes in SDS protein extractability, SDS‐accessible thiols, protein surface hydrophobicity, molecular weight distribution, and secondary structural features of proteins during mixing to bring out the molecular determinants of protein network formation in hard and soft wheat dough. Soft wheat flour and dough exhibited greater protein extractability and more accessible thiols than hard wheat flour and dough. The addition of the thiol‐blocking agent N‐ethylmaleimide (NEM) resulted in similar results for protein extractability and accessible thiols in hard and soft wheat samples. Soft wheat dough had greater protein surface hydrophobicity than hard wheat and exhibited a larger decrease in surface hydrophobicity in the presence of NEM. Formation of high‐molecular‐weight (HMW) protein in soft wheat dough was primarily because of formation of disulfides among low‐molecular‐weight (LMW) proteins, as indicated by the absence of changes in protein distribution when NEM was present, whereas in hard wheat dough the LMW fraction formed disulfide interaction with the HMW fraction. Fourier transform infrared spectroscopy indicated formation of β‐sheets in dough from either wheat type at peak mixing torque. Formation of β‐sheets in soft wheat dough appears to be driven by hydrophobic interactions, whereas disulfide linkages stabilize secondary structure elements in hard wheat dough. 相似文献
30.
Tucker KL Maras J Champagne C Connell C Goolsby S Weber J Zaghloul S Carithers T Bogle ML 《Public health nutrition》2005,8(1):87-96
OBJECTIVE: To describe food sources of nutrient intake for white and African American adults in the Lower Mississippi Delta (LMD), and their use in the development of a regional food-frequency questionnaire (FFQ) based on an earlier version of the National Cancer Institute's Health Habits and History Questionnaire. DESIGN: We ranked food sources of energy, macronutrients, vitamins and minerals, and examined portion size distributions for 842 white and 857 African American residents aged 19 years and older, using 24-hour dietary intake recall data from a telephone survey of 36 LMD counties. These values were used to develop a regional FFQ, which was then field-tested with 100 subjects and revised to improve interpretability. SETTING: The LMD region of the USA. SUBJECTS: White and African American adult residents of the LMD. RESULTS: LMD African Americans obtained more of their energy and nutrient intakes from poultry, processed meat, salty snacks, fruit drinks, pork and cornbread; and less from milk, alcohol, legumes, salad dressing, butter/margarine and sweetened tea than did white residents. Regional foods not on nationally used FFQs included grits, turnip greens, okra, ham hocks, chitterlings, crawfish, catfish, cracklings, jambalaya, potato logs, chicken and dumplings, and sweet potato pie. Based on responses during field-testing, the questionnaire was also designed to add four portion sizes for each food item, presented as questions, rather than in grid format. CONCLUSIONS: Regional food use patterns differ from national patterns and furthermore differ between African American and white adults in the LMD. The resulting Delta NIRI FFQ for Adults should contribute to improved assessment of usual intake for use in studies of diet and health in this region. 相似文献